156 HOFMEISTER, ON 



certain localities, female plants only of Mnium undulatum, 

 Mniitm punctatum, and Bryum ccsspiticium occur. In such 

 places I have found every year numerous vigorous arche- 

 gonia, but never a single fruit. When fruit is found in 

 these species, male plants are invariably to be met with in 

 the immediate neighbourhood. 



I have not yet succeeded in finding spermotozoa in the 

 central cell of the archegonia of Mosses near the germinal 

 vesicle, as I have done in Ferns.* I have, however, seen 

 in Funaria a moving spermatozoon which had penetrated 

 through a third part of the length of the neck of an arche- 

 gonium, which was ready for impregnation. 



The first symptoms of the commencement of the deve- 

 lopment of a fruit, are a considerable enlargement of the 

 germinal vesicle of the elongated ellipsoidal cell which fills 

 the large cell in the upper end of the ventral portion of the 

 archegonimn (PI. XIX, fig. 17 ; PI. XX, fig. 10), and the 

 appearance in it of a horizontal or slightly-inclined trans- 

 verse septum (PI. XIX, fig. 21 ; PI. XX, fig. 10). In Brijum 

 argenteum the upper part of the two cells divides again, 

 once or twice, by means of septa parallel to that first formed 

 (PI. XIX, fig. 22"' b). A septum inclined at a considerable 

 angle, and seated upon the uppermost of these horizontal 

 septa, is then produced. In Phascum, Funaria, and Fissi- 

 dens, this inclined septum is formed immediately after the 

 production of the first horizontal one (PL XX, figs. 11, 12). 

 The upper terminal cell of the young fruit -rudiment is then 

 divided by a septum inclined in a contrary direction to the 

 one last formed, then by another parallel to the last but 

 one, and so on. The longitudinal growth of the fruit- 

 rudiment is carried on by division of the terminal cell by 

 means of differently inclined septa (PL XIX, figs. 9 11, 

 22; PL XX, figs. 1115). 



The young rudiment of the fruit, when consisting of from 

 one to four cells, may be easily detached (PL XX, figs. 11*, 

 \'2 b ' c ). It occupies only a very small space of the upper 

 half of the ventral portion of the archegonium, in the cavity 

 of which it lies free (PL XX, figs. 11, 13). During its 



* 'Ber.der K. Sachs. Ges. d. Wiss.,' 1S54, p. 54. 



